Whey protein and carrageenan heat-set gels

ABSTRACT

This invention relates to a food ingredient, comprising a heat-set protein gel and a polysaccharide hydrocolloid which is present in an amount sufficient to influence the structure and texture of the gel, and a process for the preparation of the food ingredient.

This invention relates to food ingredients, to methods for thepreparation of such food ingredients and to food products comprisingsuch ingredients. The invention is particularly, but not exclusively,concerned with food ingredients for use in reduced-fat foods, and withthe use of dairy whey protein in the preparation of such reduced-fatfoods.

Whey is the co-product from the manufacture of dairy products whichutilise the casein proteins of milk. It contains principally lactose,minerals and the whey proteins representing approximately 20% of thetotal protein of cows' milk. The whey proteins are represented inmajority by the two proteins, α-lactalbumin and β-lactoglobulin. In aprevious invention a process was described for the fractionation ofthese major whey proteins in Australian Patent No. 616,411.

International Patent Application No. WO93/00832 (PCr/AU92/00331) (thefull disclosure of which is hereby incorporated herein) describes gelledfood products in which microparticulate suspensions are stabilised inheat-set gels for food applications. When restricted protein unfoldingoccurs as a result of heating certain globular proteins in solution,gelation may occur if specific interactions between protein moleculesenable an ordered three-dimensional network to be formed. Suchinteractions affect intermolecular cross-lining involving hydrogenbonding, ionic and hydrophobic interactions. Adjuncts to suchinteracting protein systems which affect some or all of suchcross-linking mechanisms may serve to modify the overall structure,texture and rheological problems of the gelled product.

Of the milk proteins. only certain of the whey proteins are capable ofheat-induced gelation, β-lactoglobulin is considered to be the mostimportant whey protein for gelation since it is capable of forminguniform gels of high strength. Application of the whey proteinfractionation technology developed by Pearce, yields a product which ishighly enriched in β-lactoglobulin and referred to as “β-Fraction”. Thisproduct also displays the capability of forming uniform gels of highstrength. (see Pearce, R. J. (1991) Applications of cheese whey proteinfractions. Food Research Quarterly 51; 74-91.)

Stading and Hermnansson have described the structure and appearance ofβ-lactoglobulin gels over a range of pH values and have described theclear gels formed below pH 4.0 and above about pH 6.5 as fine-strandedgels and the more turbid gels formed at intermediate pH as aggregategels. The fine stranded gels formed at low pH were brittle but in thehigher pH range were rubber-like. (see Stading, M. & Hermansson. A. M.(1991) Large deformation properties of β-lactoglobulin gel structures.Food Hydrocolloids 5: 339-352.) The ability to form heat-set gels fromfood proteins is not limited to β-lactoglobulin or to whey proteins. Forexample, heat set gelation of egg white protein is well known. Variationin the appearance and texture of such egg white gels may be achieved bymanipulation of the ionic strength and pH as has been described by Hegg,P. O. (1982) Conditions for the formation of heat-induced gels of someglobular food proteins. Journal of Food Science 47, 1241-1244. in amanner similar to that shown for β-lactoglobulin by Stading, M andHermansson, A-M. (1993) Large deformation properties of β-lactoglobulingels. Food Hydrocolloids 5, 339-352.

By combining the results, described in International Patent ApplicationNo. WO93/00832 with the results of Stading et al., we identified novelgelled food products in which the appearance and texture of the gelledproduct could be varied from clear to opaque and from elastic toinelastic according to the environmental conditions of the proteinduring the heat-gelation process. The resulting products demonstratedrheological characteristics of potential value in the formulation ofnovel foods. However, under textural analysis, these products, whetheressentially elastic or inelastic. showed distinct yield points (gelbreaking points). This property was considered undesirable for certainfood applications.

We have now found that incorporation of a polysaccharide hydrocolloidinto a heat-gelled protein results in a gelled material having amodified structure and texture which, rheologically does not display adistinct fracture point (gel breaking point). In this behavior, thegelled product exhibits the textural and Theological properties of a fat(exemplified herein by a texture profile of lard, see FIG. 13) andenables the material to be utilized as a food ingredient, e.g., atexture modifier, in food products, and especially as an ingredient inreduced-fat foods.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a texture profile for a gelled product containing nosuspended microparticles with no carrageenan.

FIG. 2 shows a texture profile for a gelled product containing nosuspended microparticles with 0.10% w/w iota-carrageenan.

FIG. 3 shows a texture profile for a gelled product containing nosuspended microparticles with 0.30% w/w iota-carrageenan.

FIG. 4 shows a texture profile for a gelled product containing nosuspended microparticles with 0.10% w/w kappa-carrageenan.

FIG. 5 shows a texture profile for a gelled product containing nosuspended microparticles with 0.30% w/w kappa-carrageenan.

FIG. 6 shows a texture profile for a gelled product containing suspendedmicroparticles with no carrageenan.

FIG. 7 shows a texture profile for a gelled product containing suspendedmicroparticles with 0.05% w/w iota-carrageenan.

FIG. 8 shows a texture profile for a gelled product containing suspendedmicroparticles with 0.10% w/w iota-carrageenan.

FIG. 9 shows a texture profile for a gelled product containing suspendedmicroparticles with 0.30% w/w iota-carrageenan.

FIG. 10 shows a texture profile for a gelled product containingsuspended microparticles with 0.05% w/w kappa-carrageenan.

FIG. 11 shows a texture profile for a gelled product containingsuspended microparticles with 0.10% w/w kappa-carrageenan.

FIG. 12 shows a texture profile for a gelled product containingsuspended microparticles with 0.30% w/w kappa-carrageenan

FIG. 13 shows a texture profile for lard.

FIG. 14 shows texture profiles of heat-set gels from whey proteinconcentrate.

FIG. 15 shows texture profiles of heat-set gels from egg white protein.

According to one aspect of the present invention, there is provided afood ingredient, characterised in that it comprises a heat-set proteingel and a polysaccharide hydrocolloid which is present in an amountsufficient to influence the structure and texture of the gel.

The heat-set protein gel is formed by heating a suitable gellableprotein. Suitable gellable proteins may be sourced from egg white, bloodserum or whey. The protein is preferably derived from a whey productrich in β-lactoglobulin, most preferably enriched β-lactoglobulin in theform of β-Fraction.

The preferred polysaccharide hydrocolloid is carrageenan, especiallyiota- or kappa-carrageenan.

A food product, in accordance with this invention can consist solely ofthe food ingredient defined above. More usually, however, the foodproduct will contain other ingredients which may be incorporated intothe protein gel or which may be simply mixed with the gel. For example,as described in WO93/00832, an edible food ingredient may be mixed with.or dispersed in, a solution of the gellable protein. before it is heatedto form the gel. Alternatively, the gel may be formed first and thenmixed with the other ingredient(s), some of which are also described inWO93/00832. Examples of such ingredients include fats or oils (which maybe incorporated in a microparticulate state) and particulate foods suchas meats or fruits.

One application of the food ingredients of the invention (referred toherein as “texture-modified gelled products”) is in the replacement offat in products to which fat is normally added. Typical of suchapplication is the replacement of added fat, such as pork back fat, inmanufactured meat products in which the added fat contributesadvantageously to the texture of the food and may be a special featureof its appearance. The texture-modified gelled products may be choppedor minced and used in manufactured meat products in a manner comparableto that currently employed for fat incorporation. For example, areduced-fat Strassburg-type sausage may be manufactured in which thetypical pieces of visible fat are replaced by the texture-modifiedgelled product.

In another application of the texture-modified gelled products inpreparing reduced-fat food materials, the texture-modified gelledproduct is added as an additional constituent of the finished productthereby effectively reducing the overall fat content of the finishedproduct. For this purpose. the texture-modified gelled product mayincorporate microparticulate oil or fat emulsion to contribute tomouthfeel and the ability to carry fat-soluble colour, flavour ornutritionally advantageous materials. Alternatively. such lipidicmaterial may be omitted if such additional contributions are notrequired. Food applications of this type may be in the form of extendedmanufactured meat products including extended ham and chopped meatproducts. In such applications the texture-modified gelled products mayprovide a desirable texture and mouthfeel and through additionallyincorporated coloured microparticulate material or soluble colourantsmay resemble in appearance the meat constituents. Such extended foodproducts alternatively may be meat analogues or manufactured fish andseafood products.

A yet further application of the texture-modified gelled products is inthe formation of new or modified foods in which food pieces of visibledimensions (i.e. not microparticulate) are incorporated and distributedthrough the gelled product. When so used, the texture-modified gelledproduct provides a base material of desirable texture which may beaugmented by incorporation of insoluble microparticulate and solublematerials to enhance the colour, flavour and nutritional value orinclusion of larger food material pieces for special appearance ortexture. This type of product may incorporate a microparticulateemulsion and pieces of food material of meat, fish, egg, vegetable orother origin.

According to another aspect, the invention provides a process for thepreparation of a food ingredient as defined above, which comprises thesteps of:

(i) preparing a solution of gellable protein at a concentration suchthat when mixed with other components of the formulation a uniform gelwill be formed on being heated;

(ii) if necessary, adjusting the pH of the protein solution to be in therange 3.5 to 7.5;

(iii) preparing a solution of an appropriate polysaccharide hydrocolloidat a concentration such that,when mixed with the solution of gellableprotein from (i) and other components of the formulation, it will resultin a fat-like texture in the resulting heat-gelled protein product;

(iv) heating the polysaccharide hydrocolloid solution to activate thehydrocolloid and subsequently holding at a temperature in the range 50°to 60° C. to maintain solubility;

(v) heating the protein solution from (i) to a temperature in the range50° to 60° C. as selected in (iv);

(vi) mixing the heated solutions from (iv) and (vi) in proportions suchthat the gellable protein content of the mixture is in the range 5 to15% and the polysaccharide hydrocolloid concentration is in the range 0to 1%;

(vii) if necessary, adjusting the pH of the mixture from (vi) to be inthe range 3.5 to 7.5, as selected in (ii);

(viii) heat treating the mixture from (vi) or (vii) at a temperature andfor a time sufficient to form a gelled product; and

(ix) cooling the heat-gelled product to ambient or sub-ambienttemperature.

If desired, an emulsion of an edible fat or oil heated to a temperaturein the range 50° to 60° C. as selected in (iv) and, if necessary, havingits pH adjusted to the value selected in (ii), can be added to themixture at step (vi).

Water-soluble substances, such as colorants, flavorants and sweetenersmay be added, if required, to the solution at an appropriate step, e.g.(i) or (ii).

Lipid-soluble colorants, flavorants and other adjuncts such asnutritionally advantageous materials may be included in the lipidicphase of any emulsion added at step (vi).

One or more insoluble microparticulate materials, which may contributeto colour, flavour or nutritive value may be incorporated into thetexture-modified gelled product, by adding them, if necessary in theform of a dispersion at an appropriate step of the process.

Insoluble materials of microparticulate or visible dimensions may alsobe included in the composite mixture prior to heat gelation.

Generally, activation of the hydrocolloid should be carried out inaccordance with the manufacturer's specifications.

The preferred parameters for the composition of the product and for theprocess of its preparation are now described in more detail.

The rigidity of the gelled product prepared by heating a solution of aprotein containing a polysaccharide hydrocolloid under controlledconditions is determined primarily by the concentration of protein. Forβ-Fraction, generally, the lower limit of concentration is 5%. whichtypically represents the minimum concentration of protein for gelformation and the upper limit is 15%, which typically represents themaximum usable hardness of a gel for use in a food system. The preferredconcentration of β-Fraction for a fat-like product is in the range 8 to12%.

We have discovered that a number of polysaccharide hydrocolloids affectthe structure and texture of whey protein/β-Fraction gels; such effectsinclude increased granularity and increased or reduced water-holdingability of the heat-set protein gel. For the preparation of fat-likeproducts for use as ingredients in reduced-fat foods, a number ofpolysaccharides have been evaluated. The incorporation of carrageenan ispreferred. While effects on the structure and texture of heat-set,β-Fraction gelled products have been observed after incorporation ofcarrageenan at all levels in the range 0 to 1%, at low levels ofincorporation (less than 0.15%) a gel strengthening effect was observed.At higher levels, further structural and textural effects of the addedcarrageenan were observed such that, while the gelled product remainedfirm and cohesive, no distinct fracture point was discernible. Thepreferred concentration of carrageenan in the gelled product is in therange 0.2 to 0.4%.

The nature of the gelled product, and particularly its texture, is alsodetermined by the pH. Generally the pH will be in the. range 3.5 to 7.5.For the gelled products comprising β-Fraction and carrageenan only tohave fat-like properties, the preferred pH is in the range 5.8 to 6.8,more preferably 5.9 to 6.2. At the lower end of this last range, i.e. pH5.9-6.1 the gelled products will have a soft texture. A firmer productis obtained at about pH 6.2.

The heat gelation process occurs: at a temperature in excess of thedenaturation temperature of β-lactoglobulin which is in the range 71 to75° C. dependent on pH and other environmental parameters. The gelledproduct may be prepared by heating at a temperature in the range 65 to100° C. The gel firmness increases with the time of heating up to amaximum value. Generally, the heating time will be in the range 5 to 120minutes. For comparative analytical purposes, the preferred heatingconditions may be stated as: immersion of the sample, tightly containedin a 50 mm diameter water-impermeable casing, in a water-bath at 90° C.for 30 minutes followed by cooling in running cold water.

As indicated above, the β-Fraction and polysaccharide hydrocolloidgelled product may optionally contain an emulsion of fat or oil. Whileapparently contributing little to the structure and texture of thegelled product, incorporation of some lipidic material assists themouthfeel of the product. Up to 20% by weight of the lipidic materialmay be present, the preferred level of addition being such that theconcentration of lipidic material in the final product is in the range 5to 10%. The emulsion may conveniently be prepared by emulsifying anedible fat or oil by homogenisation with sufficient protein ornon-protein emulsifier in aqueous dispersion at a temperature in therange 50° to 60° C. as selected in step (iv) above to form a stableoil-in-water emulsion and, if necessary, adjusting the pH to be in therange 3.5 to 7.5, as selected for step (ii).

The invention is further described and illustrated by reference to thefollowing non-limiting examples.

EXAMPLE 1

This example shows that the texture of the gelled product is altered bythe incorporation of polysaccharide hydrocolloid as evidenced by theamount of free serum, the yield point and maximum firmness together withthe rupture profile.

(i) Gelled Product with No Suspended Microparticulates

Two aqueous solutions of β-Fraction (89% protein on a dry matter basis;83% of the protein being β-lactoglobulin) were prepared at pH 6. 10 anda protein content of 9% (w/w) and warmed to 60° C. 2.5% solutions ofcarrageenan were prepared from iota-carrageenan (Viscarin ME389 Tech.spec. 448) and kappa-carrageenan (Gelcarin ME911 Tech. spec. 481), bothmanufactured by FMC Corporation, Marine Colloids Division, 1735 MarketStreet, Philadelphia Pa.19103, USA. For activation of the carrageenansin accordance with the manufacturers instructions, the solutions wereheated to 85° C. then cooled to 60° C. Composite solutions were made bycombining different weights of carrageenan solution and β-Fractionsolution to give final carrageenan concentrations in the range 0 to0.3%. A control sample was prepared without carrageenan.

Aliquots (120 ml) of each solution were placed and sealed in GlowrapPVDC seamless casing of 50 mm flat width. Each sample was heated byimmersion in a water bath at 90° C. for 30 min., cooled in runningtap-water for 1 hour, refrigerated for 15 min. and equilibrated at 20°C. Slices 30 mm in length were cut from the gelled protein product andevaluated for gel strength i.e. yield point, fracture point and maximumfirmness using a Stable Micro Systems TAXT2 texture analyser incompression mode with a test speed of 0.8 mm/sec and fitted with a flat10 mm diameter circular disc probe which was applied to the centre ofthe cut surface. A pre-weighed piece of adsorbent paper was placed undereach sample during rupture testing. After completion of each test. thesample was removed, the paper reweighed and the weight difference notedas a measure of the expelled free moisture/fat. Results are shown inTables 1.1 and 1.2 for iota-carrageenan and kappa-carrageenanrespectively. Reported values are each the mean of three determinations.

TABLE 1.1 Iota-carrageenan Compression Carrageenan Yield point* MaximumFree at yield point Figure conc. % w/w (kg) firmness (kg) moisture/fat(%) number 0.00 0.384 0.457 0.097 34.38 1 0.10 0.431 0.431 0.057 25.61 20.30 0.203 0.238 0.076 20.06 3

TABLE 1.2 Kappa-carrageenan Compression Carrageenan Yield point* MaximumFree at yield point Figure conc. % w/w (kg) firmness (kg) moisture/fat(%) number 0.00 0.384 0.457 0.097 34.38 1 0.10 0.140 0.172 0.206 20.35 40.30 0.108 0.123 0.132 19.50 5

(ii) Gelled Product Containing Suspended Microparticulates

A microparticulate dispersion. of lard in water was prepared at 60° C.by 4-stage homogenisation using an homogeniser ex Milko-Tester Mk II(Foss Electric) using β-Fraction to stabilise the emulsion at anoil:protein ratio of 45:2. The microparticulate dispersion at 60° C. wasmixed with solution of β-Fraction and carrageenan solution if requiredas in Example 1(i) to give a final concentration of 9% (w/w) of proteinand a final fat content of 7.5% (w/w).

Aliquots of each mixture were heated to stabilise the microparticulatedispersion in a gelled protein-carrageenan matrix or gelled protein onlymatrix, as in the control, under conditions as in Example 1(i). Resultsare shown in Tables 2.1 and 2.2 for iota- and kappa-carrageenansrespectively. Each of the values reported is a mean of threedeterminations.

TABLE 2.1 Iota-carrageenan Compression Carrageenan Yield point* MaximumFree at yield point Figure conc. % w/w (kg) firmness (kg) moisture/fat(%) number 0.00 0.139 0.175 0.161 19.15 6 0.05 0.499 0.499 0.064 22.77 70.10 0.432 0.432 0.065 15.93 8 0.30 0.271 0.381 0.056 14.73 9

TABLE 2.2 Kappa-carrageenan Compression Carrageenan Yield point* MaximumFree at yield point Figure conc. % w/w (kg) firmness (kg) moisture/fat(%) number 0.00 0.139 0.175 0.161 19.15 6 0.05 0.339 0.339 0.108 16.6710 0.10 0.392 0.392 0.182 18.11 11 0.30 0.209 0.280 0.122 11.72 12

Yield point is taken as the value of firmness at the point of deviationfrom linearity in the Firmness versus Distance plot shown in theaccompanying figures by the Stable Micro Systems TAXT2 texture analyser.For comparison purposes FIG. 13 shows the performance of a sample oflard tested under the same conditions as the other samples.

EXAMPLE 2

This example shows that certain other whey products rich inβ-lactoglobulin display similar ability to form heat-set gels which canalso be texture modified by inclusion of polysaccharide hydrocolloidsuch as carrageenan.

Two aqueous solutions of a whey protein concentrate derived from acidcasein whey (75.9% protein on a dry matter basis; 71% of the proteinbeing β-lactoglobulin) were prepared at pH 6.10 and a protein content of9% w/w. Iota-carrageenan was added to one of the solutions but not theother. Gelled products were prepared as in Example 1(i).

Samples were evaluated for textural properties as in Example 1(i).Result are shown in FIG. 14.

EXAMPLE 3

This example shows that protein other than whey protein displays similarability to form heat-set gels which can also be texture modified byinclusion of polysaccharide hydrocolloid such as carrageenan.

Two aqueous solutions of spray dried egg white (85.3% protein on a drymatter basis) were prepared at pH 6.10 and a protein content of 9% w/w.Iota-carrageenan was added to one of the solutions but not the other.Gelled products were prepared as in Example 1(i).

Samples were evaluated for textural properties as in Example 1(i).Results are shown in FIG. 15.

Throughout this specification and any claims which follow, unless thecontext requires otherwise, the word “comprise”, or variations such as“comprises” or “comprising”, will be understood to imply the inclusionof a stated integer or group of integers but not the exclusion of anyother integer or group of integers.

Those skilled in the art will appreciate that the invention describedherein is susceptible to variations and modifications other than thosespecifically described. It is to be understood that the inventionincludes all such variations and modifications which fall within itsspirit and scope. The invention also includes all the steps. features.compositions and compounds referred to or indicated in thisspecification. individually or collectively, and any and allcombinations of any two or more of said steps or features.

The claims defining the invention are as follows:
 1. A food ingredientcomprising a heat-set protein gel, said heat-set protein gel comprising:(a) a gellable whey protein composition comprising β-lactoglobulin; and(b) up to 1% weight polysaccharide hydrocolloid per weight heat-setprotein gel, wherein the polysaccharide hydrocolloid comprises iotacarrageenan, kappa carrageenan or a mixture thereof and wherein theamount of polysaccharide hydrocolloid is such that the heat-set proteingel does not display a distinct fracture point.
 2. A food ingredient asclaimed in claim 1 wherein the gellable whey protein composition isβ-Fraction.
 3. A food product comprising: a food ingredient comprising aheat-set protein gel, said heat-set protein gel comprising: (a) agellable whey protein composition comprising β-lactoglobulin; and (b) upto 1% weight polysaccharide hydrocolloid per weight of heat-set proteingel, wherein the polysaccharide hydrocolloid comprises iota carrageenan,kappa carrageenan or a mixture thereof and wherein the amount ofpolysaccharide hydrocolloid is such that the heat-set protein gel doesnot display a distinct fracture point; in admixture with other ediblefood ingredients.
 4. A food ingredient as claimed in claim 1, furthercomprising a microparticular oil or fat emulsion.
 5. A food product asclaimed in claim 3, wherein the other edible food ingredients.are foodpieces of dimensions visible to the naked eye.
 6. A process for thepreparation of a food ingredient as claimed in claim 1 comprising thesteps of: (i) preparing a solution of the gellable whey proteincomposition having a pH in the range of 5.8 to 6.8, wherein the gellablewhey protein composition concentration is such that when mixed withother components of the food ingredient a uniform gel will be formed onheating; (ii) preparing a solution of polysaccharide hydrocolloidcomprising iota carrageenan, kappa carrageenan or a mixture thereof, ata concentration such that, when mixed with the solution of gellable wheyprotein composition from (i) and other components of the foodingredient, it will result in a fat-like texture in the resulting foodingredient; (iii) heating the solution of polysaccharide hydrocolloidcomprising iota carrageenan, kappa carrageenan or a mixture thereof, toa temperature sufficient to activate the polysaccharide hydrocolloid,and subsequently adjusting the temperature of the solution to or holdingthe solution at a temperature from 50° to 60° C. to maintain solubility;(iv) heating the solution of gellable whey protein composition from (i)to a temperature in the range of 50° to 60° C.; (v) preparing a mixtureof the heated solutions from (iii) and (iv) having a pH of between 5.8and 6.8, the proportions of the heated solutions being such that thegellable whey protein composition content of the mixture is in the rangeof 5 to 15% and the polysaccharide hydrocolloid comprising iotacarrageenan, kappa carrageenan or a mixture thereof is up to 1%; (vi)heating the mixture from (v) to a temperature in the range of 65° to100° C. for a time sufficient to form a gel; and (vii) cooling the gelfrom (vi) to ambient or sub-ambient temperature to form the foodingredient.
 7. A process as claimed in claim 6, further comprisingadding an emulsion of an edible fat or oil heated to a temperature inthe range of 50° to 60° C. and having a pH in the range of 3.5 to 7.5 tothe mixture at step (v).
 8. A process as claimed in claim 7, furthercomprising adding lipid soluble material selected from the groupconsisting of lipid soluble colorants and lipid soluble flavorants tothe edible fat or oil.
 9. A process as claimed in claim 6, wherein atleast one of water soluble colorants, water soluble flavorants or watersoluble sweeteners are added to the solution of gellable whey proteincomposition or the polysaccharide hydrocolloid solution.
 10. A foodingredient as claimed in claim 1 wherein the carrageenan is present in aconcentration of 0.2 to 0.4% weight per weight.
 11. A food ingredient asclaimed in claim 4, further comprising one or more additional sweetenerslipid soluble colorants, flavorants or nutritionally advantageousadjuncts.
 12. A food ingredient as claimed in claim 1, furthercomprising one or more additional water soluble colorants, flavorants orsweeteners.
 13. A process for preparing a food product as claimed inclaim 3 comprising the steps of: (i) preparing a solution of a gellablewhey protein composition having a pH in the range of 5.8 to 6.8, whereinthe gellable whey protein composition concentration is such that whenmixed with other components of the food ingredient a uniform gel will beformed on heating; (ii) preparing a solution of polysaccharidehydrocolloid comprising iota carrageenan, kappa carrageenan or a mixturethereof, at a concentration such that, when mixed with the solution ofgellable whey protein composition from (i) and other components of thefood ingredient, it will result in a fat-like texture in the resultingfood ingredient; (iii) heating the solution of polysaccharidehydrocolloid comprising iota carrageenan, kappa carrageenan or a mixturethereof, to a temperature sufficient to activate the polysaccharidehydrocolloid, and subsequently adjusting the temperature of the solutionto or holding the solution at a temperature from 50° to 60° C. tomaintain solubility; (iv) heating the solution of gellable whey proteincomposition from (i) to a temperature in the range of 50° to 60° C.; (v)preparing a mixture of the heated solutions from (iii) and (iv) having apH of between 5.8 and 6.8, the proportions of the heated solutions beingsuch that the gellable whey protein composition content of the mixtureis in the range of 5 to 15% and the polysaccharide hydrocolloidcomprising iota carrageenan, kappa carrageenan or a mixture thereof isup to 1%; (vi) heating the mixture from (v) to a temperature in therange of 65° to 100° C. for a time sufficient to form a gel; (vii)cooling the gel from (vi) to ambient or sub-ambient temperature to formsaid food product, and wherein at least one edible food ingredientselected from: (A) one or more microparticulate insoluble materials orsoluble materials which are colorants or flavorants; and (B) insolublefood pieces of dimensions visible to the naked eye; is added to thesolutions produced at any one of steps (i) to (v).
 14. A process forpreparing a food product comprising mixing a food ingredient comprisinga heat-set protein gel; said heat-set protein gel comprising: (a) agellable whey protein composition comprising β-lactoglobulin; and (b) upto 1% weight polysaccharide hydrocolloid per weight of heat-set proteingel, wherein the polysaccharide hydrocolloid comprises iota carrageenan,kappa carrageenan or a mixture thereof and wherein the amount ofpolysaccharide hydrocolloid is such that the heat-set protein gel doesnot display a distinct fracture point; with at least one of: (i) one ormore microparticulate insoluble materials or soluble materials which arecolorants or flavorants; or (ii) insoluble food pieces of dimensionsvisible to the naked eye.
 15. A food ingredient comprising a heat-setprotein gel, said heat-set protein gel comprising: (i) a gellable wheyprotein composition comprising at least 71% weight β-lactoglobulinper,weight of whey proteins; and (ii) up to 1% weight polysaccharidehydrocolloid per weight of heat-set protein gel, wherein thepolysaccharide hydrocolloid comprises iota carrageenan, kappacarrageenan or a mixture thereof and wherein the amount ofpolysaccharide hydrocolloid is such that the heat-set protein gel doesnot display a distinct fracture point.
 16. A food ingredient comprisinga heat-set protein gel, said heat-set protein gel comprising: (i) 5 to15% weight gellable whey protein composition per weight of heat setprotein gel, said gellable whey protein composition comprisingβ-lactoglobulin; and (ii) up to 1% weight polysaccharide hydrocolloidper weight heat-set protein gel, wherein said polysaccharidehydrocolloid comprises iota carrageenan, kappa carrageenan or a mixturethereof and wherein the amount of polysaccharide hydrocolloid is suchthat the heat-set protein gel does not display a distinct fracturepoint.
 17. A food ingredient comprising a heat-set protein gel, saidheat-set protein gel comprising: (i) 5 to 15% weight gellable wheyprotein composition per weight of heat-set protein gel, said gellablewhey protein composition comprising β-lactoglobulin; and (ii) up to 0.2%to 0.4% weight polysaccharide hydrocolloid per weight of heat-setprotein gel, wherein said polysaccharide hydrocolloid comprises iotacarrageenan, kappa carrageenan or a mixture thereof and wherein theamount of polysaccharide hydrocolloid is such that the heat-set proteingel does not display a distinct fracture point.
 18. A food ingredientcomprising a heat-set protein gel, said heat-set protein gel comprising:(i) 5 to 15% weight gellable whey protein composition per weightheat-set protein gel, said gellable whey protein composition consists ofβ-Fraction; (ii) up to 1% weight iota carrageenan, kappa carrageenan ora mixture thereof, per weight heat-set protein gel, wherein the heat-setprotein gel does not display a distinct fracture point.
 19. A foodingredient comprising a heat-set protein gel, said heat-set protein gelcomprising: (i) 5 to 15% weight gellable whey protein composition perweight of heat-set protein gel, wherein said gellable whey proteinconsists of β-Fraction; (ii) 0.2 to 0.4% weight iota carrageenan, kappacarrageenan or a mixture thereof, per weight heat-set protein gel,wherein the heat-set protein gel does not display a distinct fracturepoint.
 20. The food ingredient as claimed in claim 1 wherein theheat-set protein gel has a compression at its yield point of 10-20%. 21.The food ingredient as claimed in claim 20 wherein the heat-set proteingel has a firmness at its yield point of 0.1-0.3 Kg.
 22. The foodingredient as claimed in claim 21 wherein the heat-set protein gel has amoisture loss of 0.05-0.15% when compressed.